This one is something special. I’d call it a flat pattern, too. Very well done, sir!
Source GetDiscount
Drawn in Paint.net and vectorised in Vector Magic.
Source Firkin
Prismatic Groovy Concentric Background 3 No Black
Source GDJ
The unit cell for this seamless pattern can be had in Inkscape by selecting the rectangle and using shift+alt+i.
Source Firkin
This was formed by distorting an image of a background on Pixabay.
Source Firkin
The classic notebook paper with horizontal stripes.
Source Are Sundnes
One more in the line of patterns inspired by Japanese/Asian styles. Smooth.
Source Kim Ruddock
Washi (和紙?) is a type of paper made in Japan. Here’s the pattern for you!
Source Carolynne
Inspired by a 1930s wallpaper pattern I saw on TV.
Source Firkin
The image is a remix of "edo pattern-samekomon".I changed the color of dots from black to white and added BG in light-brown.
Source Yamachem
Sweet and subtle white plaster with hints of noise and grunge.
Source Phil Maurer
Seamless Prismatic Pythagorean Line Art Pattern No Background. A seamless pattern that includes the original tile (go to Objects / Pattern / Pattern To Objects in Inkscape's menu to extract it).
Source GDJ
A seamless texture traced from an image on opengameart.org shared by Scouser.
Source Firkin
A simple bump filter made upon request at irc #inkscape at freenode. Made a screen capture of the making here: https://youtu.be/TGAWYKVLxQw
Source Lazur URH
Based on several public domain drawings on Wikimedia Commons. This was formed from a rectangular tile. The tile can be accessed in Inkscape by selecting the rectangle and using shift-alt-i
Source Firkin
A bit like some carbon, or knitted netting if you will.
Source Anna Litvinuk
The image depicts a seamless pattern of a snow crystal.I referred to a book called ”sekka-zusetsu” or "雪華図説" which means an illustrated explanation about snow crystals.This book was published in 1832 (天保3年) or Edo period.For more about "雪華図説",see here:dl.ndl.go.jp/info:ndljp/pid/2536975
Source Yamachem
Prismatic Snowflakes Pattern 3 No Background
Source GDJ
Adapted heavily from a JPG that was uploaded to Pixabay by Viscious-Speed.
Source Firkin
Number 1 in a series of 5 beautiful patterns. Can be found in colors on the submitter’s website.
Source Janos Koos
Paper model of a tetrahedron. Modelo de papel de um tetraedro.
Source laobc
A repeating background for websites with a texture of black groove stripes.
Source V. Hartikainen
Textured Red Brown Plastic, Free Background Pattern. Although there's already enough plastic in our lives, let's bring it to the web too.)
Source V. Hartikainen
A seamless pattern the unit cell for which can be had by selecting the rectangle in Inkscape and using shift+alt+i.
Source Firkin
Pattern produced in Paint.net using the Vibrato plug-in.
Source Firkin